People are generally aware of the most common causes of hallucinations, like schizophrenia and a really high fever. But lesser known are the more rare causes; here are six you probably haven't heard about.

Guinea has reached the end of active Ebola virus transmission, the World Health Organization said on Wednesday, the second such declaration from the country at the epicenter of the world's worst outbreak of the disease.

The world’s scientific community is focused on how to improve detection and responses to emerging diseases such as Zika virus and Ebola. So what can we learn from the most recent large-scale outbreaks?

The World Health Organization (WHO) has declared the Ebola emergency over, but action is still needed to fully develop effective vaccines and prepare the world for future outbreaks, experts said on Thursday.